I emphasize on SOMETIMES, few lies are acceptable!

He: Had your lunch?
She: Yup! I had.
No.. I'm still working -_-

She: Are you coming early today?
He: I don't think so! -_-
Open the door.. I'm right infront of it!

He: Are you jealous?
She: yes! I am! :/
No... I'm not.. I trust you!

He: Did you forget my birthday?
She: I'm so sorry.. I have just recharged my phone.. I was about to call you
Sorry.. I forgot!